Spontaneous combustion is being blamed for a fire at a Mt Maunganui house yesterday.

Seamus and Anne McKenna got home to find four fire crews tackling a blaze that gutted a spare bedroom and scorched their newly-decorated kitchen.

Mt Maunganui fire station officer Lindsay Nicol said it appeared dust in a sander left in the bedroom self-ignited about 2pm.

Mr McKenna, 37, said he and his wife were "completely stunned".


"The fire guys told us it was spontaneous combustion," said the self-employed builder.

"I've never heard of anything like this happening before. I thought I had taken all the right safety precautions and can't believe this could even happen."

Mr McKenna said after using the sander in the lounge he turned it off and stored it unplugged in the spare bedroom intending to start on that room next.

The couple are insured but he had no idea what the repair bill would be.

Some fish in a tank in the bedroom died in the fire but Mr McKenna was last night counting his blessings.

"You have to look at the bright side don't you. It's only timber and nails at the end of the day. Another 10 minutes and the whole house could have been gutted. It was really lucky this did not happen at night while we were sleeping.''

There were smoke alarms in the house but one in the lounge next to the gutted bedroom was taken down during renovations.

Mr Nicol said it was lucky a neighbour noticed the smoke and the fire station was just around the corner.

"Another couple of minutes and the whole house would have been engulfed in flames."

He said the damage was confined to one bedroom and a bit of scorching in the kitchen but the fire showed how essential smoke alarms were.

He urged people to cover them with cloths rather than deactivate them during renovations.